Apparatus for injection molding

ABSTRACT

An injection molding apparatus including a clamping unit, a supporting frame and a driving device for pivoting the supporting frame and the clamping unit engaged therewith, wherein in one embodiment the supporting frame includes a clamping unit stabilizing arm and in another embodiment a part of the clamping unit is utilized as a stabilizing arm, and wherein in one embodiment the driving device is a hydraulic type actuator and in another embodiment the driving device is a manually actuatable spindle.

ijited w 'aterrt 1 1 11} 3,751,203 Aug. 7, 1973 Hehl [54] APPARATUS FORINJECTION MOLDING 3,534,442 10/1970 Mahle 425/242 3,464,091 9/1969Bie1fe1dt 425/246 1 lnvemor- H h Swdiuns 7. 152, 1 3,574,400 7/1972Sauerbruch'et a1 425/242 x Lossburg/Wurttemberg, Germany Filed: June.1971 FOREIGN PATENTS OR APPLICATIONS 1,214,393 4/1966 Germany 425/242[211 App]. No.: 156,856

Primary Examiner.1. Spencer Overholser [30] Foreign A fi ti priorityData Assistant Examiner-David S. Safran July 2, 1970 Germany P 20 32789.3 A'mr"ey spencer Kaye [52] US. Cl.... 425/190, 425/242, 425/450[57] ABSTRACT [51] Int. Cl 1329i l/00 An ]Ct1011 moldmg apparatusincluding a clamping Fleld of Search unit a pp g frame and adrivingdevice for p 425/192 193 ing the supporting frame and the clamping unitengaged therewith, wherein in one embodiment the sup- [56] References dporting frame includes a clamping unit'stabiiizing arm UNITED STATESPATENTS and in another embodiment a part of the clamping unit 3,373,4593/1968 Hehl 425/450 x is utilized as'a stabilizing arm, and wherein inone em- 3,350,746 11/1967 Blumer 425/247 bodiment the driving device isa hydraulic type actua- 3,669,599 6/1972 Snider BI 425/450 X tor and inanother embodiment the driving device is a 3,564,658 2/1971 Hehl 425/188ll actuatable i d] 2,490,625 12/1949 Hall 425/242 X v p 2,575,190 11/1951 20 Claims, 14 Drawing Figures Sedgwick 425/242 X PATENTED37515203 saw a or 9 INVENTOR. Karl Hehl ATTORNEYS PAIENTEL sum 5 OF 9 Nm m 6 we 8 W c w in I 0 w K M u 5 Y 6, 8 4 $-O Fig. 7

ATTORNEYS.

Pmmwm: H915 3.751.203

SHEET 7 BF 9 mvsnroa. Kori Hehl ATTORNEYS.

BACKGROUND OF THE INVENTION The present invention relates to injectionmolding apparatus, and more particularly to an improvement oftheinjection molding apparatus described and claimed inmy U.S. Pat. No.3,564,658.

If in the device of the aforementioned patent the clamping unit ispivoted from the horizontal position to the vertical position, thecenter of gravity of the clamping unit, which in the horizontal positionis located in the machine base, leaves the bottom area of the machinebase. Because of system inertia, the clamping unit has the tendency tocontinue moving in the pivoting direction and to tip over. In theaforementionedpatent, the tip over problem is prevented by joining thedriving member of ,a pivoting device to the clamping unit at a distancefrom the pivot axis so that the driving member can hold the clampingunit in its vertical position. Since the point of juncture for thedriving member of the pivoting device is disposed relatively close tothe pivot axis of the clamping unit, substantial stresses may occur inthe driving member at that point. Under certain circumstances a whippingphenomenon appears during pivoting of the clamping unit as well as whenthe unit is in the vertical position. For example, it was found thatwhen the driving member of the pivoting de vice is suddenly stoppedafter pivoting of the clamping unit and this clamping unit is heldinvertical position by fixing the supporting frame, 14 the relative largemass of the clamping unit may cause an oscillation of that unit, becausethe distance between the two fixing points for the frame is relativesmall.

It would, therefore, be desirable to provide aclamping unit which isstabilized to a substantial degree against the whipping phenomenaexemplarily discussed above.

According to the present invention, the apparatus as disclosed andclaimed in the aforementioned patent is now improved to such an extentthat it now exhibits a greater stabilization of the clamping unit thanhas heretofore been feasible. This is accomplished by providing theclamping unit support with a stabilizing arm for stabilizing thevertically oriented clamping unit.

SUMMARY OF THE INVENTION It is, therefore, an object of the presentinvention to provide an injection molding apparatus in which theclamping unit is stabilized to an extent not heretofore possible.

It is another object of the present invention to provide an injectionmolding apparatus in which a stabilizing arm formed as part of aclamping unit support is utilized to stabilize the clamping unit.

It is still another object of the present invention to provide aninjection molding apparatus in which a stabilizing arm formed as part ofthe clamping unit is utilized to stabilize the clamping unit.'

It is yet another object of the present invention to provide aninjection molding apparatus in which a driving device is utilized tocontrol the pivoting motion of the stabilizing arm and clamping unit.

These and other objects of the present invention are accomplished byprovision of an injection molding apparatus including a clamping unitincluding a stationary member and a movable member, a supporting frameand a driving device. The supporting frame includes in one embodiment astabilizing arm which serves to stabilize the clamping unit when theclamping unit is disposed in its vertical orientation. In anotherembodiment, the stabilizing arm is made integral with or attacheddirectly to the clamping'unit. In either embodiment the stabilizing armis abutted at at least one point on the machine base, on which both theclamping unit and stabilizing arm are mounted for pivotal movement, at adistance from the pivot axis. With such a configuration the clampingunit is sufficiently stabilized in all operating positions. For example,in the vertical position, the clamping unit is supported over the entirelength of the stabilizing arm or at the free end of this arm. In anycase, there thus results a vertical fixation of the clamping unit bymeans of fixing points which are spaced relatively far apartvfrom oneanother. This in particular relieves the driving device from the highstress loading of the clamping unit, so that the above-mentionedwhipping phenomena is effectively eliminated. Increased stabilization,particularly for heavier machines, is also provided according to thepresent invention in that in a machine of the above-mentioned type, thesupporting frame or the stationary member is provided with a stabilizingarm which supportsthe movable member With this stabilizing arm thepiston rods which bear the movable member are relieved of the weight ofthe movable member and the mold-section carried thereby, particularlywhen the clamping unit is in the horizontal position.

Preferably,'the stabilizing arm supporting the vertically orientedclamping unit simultaneously serves as the stabilizing arm and asupporting arm for the movable member.

Advantageously in one embodiment the supporting frame which comprises aframe structure includes a pivot portion and parallel or coaxial leverarms extending on either side of the pivot portion.

In another embodiment the supporting frame comprises a frame structureas above and a further pivot arm which branches off at an angle in thearea of the pivot portion. The end of the latter pivot arm is inengagement with a pivot pin with a setting spindle axially mounted onthe machine base.

In a furtherembodiment of the invention the supporting frame is designedas a two-armed toggle lever with one lever arm slidably mounting thestationary member and the other angled lever arm engaging by means of apivot pin a setting spindle. The setting spin-- dle is additionallymounted to the machine base through a pivot pin.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of theapparatus, according to the invention, which shows a clamping unit andsupporting frame horizontally disposed with a driving device forpivoting the clamping unit and supporting frame.

FIG. 2 is a side view of the apparatus of FIG. 1 showing the clampingunit and the supporting frame rotated FIG. 3 is an end view of thesupporting frame of FIGS. 1 and .2 viewed in the direction of FIG. I.

FIG. 4 is a side view of the. supporting frame of FIG.

FIG. 5 is a plan view-of the supporting frame of FIG. 1.

FIG. 6 is a side view of the apparatus of FIG. 1, with an alternatedevice for pivoting the clamping unit and supporting frame.

FIG. 7 is a side view of the apparatus of FIG. 2, with the alternatedevice for pivoting the clamping unit and supporting frame shown in FIG.6.

FIG. 8 is a side view of the apparatus, according to the invention,which shows a clamping unit and an alternate embodiment of thesupporting frame along with the device for pivoting the clamping unitand the supporting frame shown in FIGS. 6 and 7.

FIG. 9 is a partial cross-sectional view taken along line 99 of FIG. 8showing means for fastening the clamping unit to the supporting frame.

FIG. 10 is a side view of the apparatus of FIG. 8 showing the clampingunit and the supporting frame rtated 90.

FIG. 11 is a side view of an alternate embodiment of the supportingframe.

FIG. 12 is a plan view of the supporting frame of FIG. 11.

FIG. 13 is an end view of the supporting frame of FIGS. 11 and 12.

FIG. 14 is a side view of the apparatus, according to the invention,showing the supporting frame of FIGS. 1 1-13 and a clamping unitvertically disposed but without the device for pivoting the clampingunit and supporting frame.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In all embodiments, theclamping unit is mounted on the machine base 1 to be pivotal about anaxis 11 of a pivot pin 3 through an angle of approximately 90. At leastone injection unit 91 (shown, for example, in FIG. 8) is coaxiallyconnectable to the clamping unit 10 so as to operate transverse to theseparating groove of the mold (not shown).

Referring to FIGS. 1 and 2, clamping unit 10 includes essentially astationary member 16, a movable member 33 and two pairs ofinterconnecting piston rods 29 and 30. The stationary member 16 includestwo pairs of pressure cylinders 12 and 13. These pressure cylinder 12and 13 produce therein the closing pressure for the mold. Piston rodpairs 29 and 30 extend from the pressure cylinder pairs 12 and 13outwardly thereof. At their end away from the pressure cylinders thepiston rods extend through and are attached to the movable member 33 bymeans of bolts 64. The movable member 33 in turn has a pair of studs 73,whose purpose will be described hereinafter. The chambers of the pairsof pressure cylinders 12 and 13 are sealed at one end by means of twopairs of cylinder covers 22 and 23. The piston rods 29 and 30 extendthrough the covers 22 and 23 as sections 29' and 30.

The supporting frame 14 in one embodiment (FIGS. 3 5 and 11 14) isconfigured as a two-armed lever. It includes three spaced transverseplates 71, 72 and 73 and parallel arms 74, 75 and 74', 75' extendingfrom the ends of and between the transverse plates 71, 72 and 73. Thetransverse plates 71, 72 and 73 increase the structural stability of thesupporting frame. The arms 74, 75 and 74, 75' include therein pairs ofgrooves or slide ways or guides4, 5 and 4', 5 respectively.

The pairs of grooves or slide ways or guides 4, 5 and 4', 5' overlap inthe area b-b (FIG. 5). The overlap forms a plane which is disposed inthe uppermost plane of the machine base 1. The stationary member 16 ismounted in the pair of grooves or guides 4, 5, with the lever arms 74'and 75' serving as stabilizing arms extending with their pair of groovesor slide ways 4', 5 from the pivot axis 11 in the direction of themovable member 33. The movable member 33 is displaceably mounted in thepair of grooves or slide ways 4', 5' with the aid of the studs 73. Thestuds are sliding on the plane surface of the sliding ways.

The pairs of grooves or slide ways or guides 4, 5 and 4', 5' may lie indifferent planes. For example, the pair of slide ways 4', 5' may bedisposed at a greater distance from the axis aa than is the pair ofguides 4, 5, (FIG. 4). In some cases it may be advisable, however, toprovide continuous guides which are disposed in one plane and to designthe supporting frame 14 in such a manner that it is symmetrical withrespect to a plane which passes through the pivot axis 11. That is, theplane of symmetry would be perpendicular to the plane of the pairs ofguides and pass through axis 11.

It is not necessary that the studs 73 engage the pair of grooves 4', 5on the stabilizing arms 74, 75'. These studs may, for example, simplyslide on the surface of the stabilizing arms 74', 75.

Sleeve-type connecting elements 6, 7, which have a preferablyrectangular inner bore and reinforced platelike protrusions 6, 7', servefor the connecting of an injection unit to the stationary member 16.These protrusions are attached to and extend from arms 74, 75 of thesupporting frame'14. The supporting frame 14 has protruding therefromtwo lugs 14' through which the pivot pin 3 extends for pivotallyattaching the supporting frame 14 to the machine base 1 of the upperedge of the frontal side thereof.

The supporting frame 14 with its transverse plates 71, 72 and 73 may bemade as one piece. Alternatively, instead of the supporting frame it ispossible to use a closed mold piece which extends on both sides of thepivot axis 11 also in the form of a two-armed lever. That is, thestationary member 16 could be pivotally connected directly to themachine base I.

The clamping unit 10 is axially displaceable along the pairs of groovesof the supporting frame by means of a setting spindle (not shown).

Further injection units (not shown) which cooperate with the separatinggroove of the mold as described in the afore mentioned patent, may beguided with the aid of a carriage on stationary member 16 in a directionwhich extends parallel to the centerline aa of the clamping unit 10. Thecarriage is joined with sleeves 6, 7. In this way it is possible to setthe injection units for operation with the separating groove of themold. Since the injection unit connected in sleeves 6, 7 cannot beadjusted in height, the separating groove is brought into coincidencewith the injection axis of the injection unit by axial displacement ofthe vertically oriented clamping unit 10 (FIG. 2).

To pivot the clamping unit 10, actuators are provided which areconnected with the machine base 1 by a pivot pin 42, so that theactuators are held inclined to the vertical axis of the machine base 1.The actuators comprise a threaded spindle 36 which may be joined to thesupporting frame 14 in the region b-b and a hydraulic motor 31. Thethreaded spindles are driven to extend in an axial direction by means ofthe hydraulic motors 31, which are in turn actuated in any conventionalmanner. The threaded spindles are preferably driven by a pinion (notshown) engageable therewith. It should be understood, however, thatother driving relationships could be utilized to effect the axialextension of the spindles as desired. The actuators 70 each include aprotective sleeve 39 into which the spindles 36 extend.

The plate-shaped connecting bar 72 between longitudinal arms 74, 75 isprovided with a cut-out 81 for receiving therethrough the cylinder of aninjection unit held in the connecting sleeves 6, 7. All the free ends oflever arms 74' and 75 and abutment means 82 are provided for engaging astop means 82" mounted on the machine base 1. The engagement of theabutment means 82 and stop means 82" serves to provide a load paththrough the lever arms 74' and 75' to the machine base 1, therebysubstantially unloading the actuators 70 and thereby significantlyimproving the stability of the apparatus when the clamping unit isvertically oriented. Additionally, the abutment means 82 and the stopmeans 82" are provided with aligning bores '82 and 82" respectively, forreceiving a fastening bolt (not shown) if desired to insure a betterengagement of the abutment andstop means.

Turning to the embodiment shown in FIGS. 6 and 7, it can be seen thatinstead of the actuators 70, a driving device 80 is provided whichpermits manual pivoting of the clamping unit 10. The device 80 comprisesa pivot arm 83 which is connected to the supporting frame 14 by thepivot pin 3 and extends perpendicularly therefrom. The free end of thepivot arm 83 has pivotally mounted within a bore 83 a pivot pin 84. Thepin 84 is provided with a threaded bore 84' into which one end of asetting spindle 85 is received. The setting spindle 85 is disposed inthreaded engagement with the inner threads of the pin bore 84'. Theother end 85 of the setting spindle 85 passes through a pivot pin 86which is pivotally mounted within the machine base 1. The pivot pin 86includes a bore 86 for receiving end 85' of the setting spindle 85. Theadjustment of the setting spindle 85 is accomplished by means of theaxial abutments 87 which are in contact with both sides of the pivot pin86 and the square end 85" of the setting spindle 85 which serves as anengagement surface of a pivot lever (not shown). The pivot lever could,for example, engage the square end 85 and rotate the setting spindle 85by either rotating the lever or by swinging the lever through respectivearcs. As a result, the pivot arm 83 will advance axially along thesetting spindle 85. Because the setting spindle 85 is connected tobearing bolt 86 it can pivot therewith so that the pivot arm 83 will bepermitted to follow its natural arc in pivoting about axis 11 whileaxially advancing along setting spindle 85. Of course at any given axialposition, the pivot arm 83 is held fast by the thread engagement of thebore 84' and the setting spindle 85. The abutment and stop means aresimilar to that shown and explained with respect to the embodiment ofFIGS. 1 and 2.

In still another embodiment shown in FIGS. 8 10, a two-armed togglelever 89 is utilized. The toggle lever 89 includes two levers 89' and89". A supporting frame 88 which includes cylinder blocks 88', 88" andstabilizing arms 88 is guided on lever arm 89' (FIG; 9). The stabilizingarms.88", which support the movable member 33, is preferably an integralcomponent of the cylinder blocks 88". However, it should be-understood,

that the arms 88" may also be formed by one or a plurality of supportingstruts which are fastened to the cylinder blocks. The other arm 89" ofthe toggle lever 89 is perpendicular to arm 89' and serves as astabilizing arm. The stabilizing arm 89" alsoserves as a pivot lever andis part of a device for pivoting the clamping unit 10 which correspondsto that shown in the embodiment according to FIGS. 6 and 7. When theclamping unit 10 is in the vertical position, the free :end 90 of thearm 89" engages an abutment on the machine base I (FIG. 10).

When the clamping unit 10 is to transform from the horizontal position(FIG.8) to the vertical position (FIG. 10), first is to perform thepivoting about the axis 3 and then the cylinderblock 88" is to move inaxial direction until the position line of the mould lies in the axis ofthe injection unit 91 which works into this position line.

An exchangeable injection unit 91 may be connected coaxially to theclamping unit 10 (FIG. 8)..In addition, it may be held in rectangularoperating position, by the connecting sleeves 6 of the pivotal moldpiece 89, 90. In both cases the injection unit is supported by a base92. FIG. 9 shows how the cylinder block 88" is guided in the area of itsstabilization arm 88" by the arm 89' of the toggle lever 89. It canparticularly be seen how the stabilizing arm 88" and thus the clampingunit 10 can be clamped to the arm 89' of the toggle lever in a certainaxial position by means of screw bolts 94 and abutment elements 93.

Turning now to FIGS. 11 12 there can be seena supporting frame 1 14which is a modified embodiment of supporting frame 14. Supporting frame114 is provided, in addition to the connecting members 6, 7 with afurther pair of connecting members 6", 7 for connecting an injectionunit operating into the separating groove of a mold. The injection unitis fastened to the arms 74'75 of supporting frame 114 by the connectingmembers 6", 7". Both pairs 6, 7, 6", 7" of connecting elements aredisposed symmetrically to the pivot axis 1 1. Two pairs of eyes 34, 34are provided in the arms 74, and 74, 75 respectively for connecting theactuators or devices shown in FIGS. 1 and 2 or 6, 7, 8 and 10respectively.

It is sometimes advisable, in order to increase the versatility of aninjection molding apparatus to be able to invert the position of theclamping unit 10 from that shown in FIG. 2 to that shown in FIG. 14.With a position of the clamping unit 10 according to FIG. 14 it is veryeasy, for example, to place insert portions or cores onto the immovablefrontal face 98 of the stationary member 16 or on the mold half fastenedto this frontal face without incurring the danger of a change inposition due to shock. This is not the case in a position'of theclamping unit as shown in FIG. 2, because the cores, which are subjectedthe effect of gravity cannot be positioned on the stationary member 16.Moreover, the center of gravity of the entire assembly is lower for aposition of the clamping unit 10 according to FIG. 14

than for a position of the clamping unit 10 according to FIG. 2. Thisgives rise to a better stabilization of the entire assembly. I

The clamping unit 10 together with the supporting frame 14 can bepivoted by about an axis z-z so that the pair of grooves 4, 5 which aredisposed above the line d--d of the machine base 1 when the clampingunit is in the vertical position will then lie below the line dd. Such aposition is shown in FIG. 14. The pivoting can be achieved by pullingthe pivot pin 3 out from lugs 14, and lifting the clamping unit 10 andthe supporting frame 14 by a lifting device and pivoting them about axiszz. The pivoted clamping unit and supporting frame are then replaced onthe machine base in such a manner that the pivot pin 3 can again beplaced through the lugs 14. The orientation now has the clamping unit atthe bottom and the movable member at the top such as is shown in FIG.14.

If the supporting frame 114 is so designed, however, so that it issymmetrical about axes x-x and yy in FIG. 12 at least insofar as havingtwo sets of connecting members and identical pairs of grooves, then itwill not be necessary to pivot the supporting frame 1 14 in order tobring the clamping unit 10 from a position according to FIG. 2 into aposition according to FIG. 14 since the portions 74, 75, and 4, disposedon the one side of the pivot axis 11 are identical with the portion 74',75' and 4', 5 disposed on the other side of the pivot axis. In this way,the stationary member of the clamping unit may be selectively mounted inthe pair of grooves 4, 5 of the arms 74, 75 or in the pair of grooves 4,5 disposed in extension of the pair of grooves 4, 5.

With such a configuration of the supporting frame 114 its length isdesirably so dimensioned that the clamping unit 10 can be displaceableinto a position in which its center of gravity lies above the base areaof the machine base 1.

Advantageously the movable member 33 is provided with connectingelements 99 for the connection of a further injection unit in adirection coaxial with the clamping unit so that it is possible, whenthe clamping unit is in a position as shown in FIG. 14, to inject intothe mold also in a direction transverse to the separating groove.

In the embodiment shown in FIG. 14, the supporting frame 114 is providedwith eyes 34, 34 as described above, so that actuators or other devicesmay be attached for pivoting the clamping unit 10 and pivotal mold piece114 about axis 11.

It will be understood that the above description of the presentinvention is susceptible to various modifications, changes andadaptations, and the same are intended to be comprehended within themeaning and range of equivalents of the appended claims.

I claim:

1. Apparatus for injection molding, comprising in combination:

a. a base;

b. a mold clamping unit including a stationary member, a movable memberand means connecting said members;

c. support means for carrying said members and securing them to saidbase, said support means including 1. a pivot portion for connectingsaid support means to said base for pivotal movement relative theretoabout an axis thereof;

2. parallel side members extending from said pivot portion on eitherside thereof, said side members including means for abutting said baseat least at one point spaced from said axis; that portion of each sidemember that is disposed on one side of said pivot portion constitutes astabilizing arm supporting said movable member;

3. guide means provided on and along said members, said guide meansincluding grooves; said stationary member engaging said grooves on oneside of said pivot portion; said movable member slidably engaging saidgrooves on the other side of said pivot portion; said support meansbeing symmetrical on both sides of said pivot portion with respect tosaid grooves, so that said stationary member is engageable with sidemembers on either side of said pivot portion;

d. drive means connected to said base and said supporting means forpivoting said supporting means about said axis in one direction so thatsaid means for abutting engages said base at said at least one point;and

e. two pairs of connecting means on each side of said pivot portion forthe connection of said drive means in the two possible positions of saidstationary member; said two pairs of connecting means forming part ofsaid support means.

2. Apparatus for injection molding, comprising in combination:

a. a base having an outline obtained by vertical projection; i

b. a mold clamping unit including a stationary member, a movable memberand means connecting said members;

c. pivot means attached to said base;

(1. arm means swingable about said pivot means in a substantiallyvertical plane to selectively assume a first, or substantiallyhorizontal position and a second position disposed at least about withrespect to said first position, said arm means having 1. a firstelement, at least a major part of which extending from said pivot meansin a first direction; said major part being located over and within saidoutline in said first position of said arm means; said first elementcarrying said stationary member;

2. a second element, constituting a stabilizing arm, at least a majorpart of which extending from said pivot means in a second direction thatis opposite to said first direction; said major part of said secondelement being located externally of said outline in said first positionof said arm means; said movable member supported by and travelling alongsaid second element during operation of said apparatus;

. guide means provided on said second element of said arm means tocooperate with said movable member for guiding the latter in its travel;and

f. abutment means on said major part of said second element to engagesaid base in said second position of said arm means.

3. An injection molding apparatus as defined in claim 2, furthercomprising means for adjustably immobilizing said stationary memberalong said first portions of said arm means.

4. An injection molding apparatus as defined in claim 2, wherein saidarm means are formed of a plurality of parallel spaced arms.

5. An apparatus for injectionmolding as defined in claim 2, wherein saidstabilizing arm is part of said sta-.

tionary member.

6. An injection molding apparatus as defined in claim 5, furthercomprising a toggle lever having a pivot portion and two arms; saidpivot portion consituting said pivot means; one arm of said toggle leverconstituting said first element of said arm means; the other arm of saidtoggle lever constituting an additional stabilizing arm disposedsubstantially normal to said second element of said arm means, saidadditional stabilizing arm, when said clamping unit is verticallyoriented with respect to said base, abuts with a free end thereof aportion of said base.

7. An'injection molding apparatus as defined in claim 6 wherein anadjusting spindle engages said other arm of said toggle lever and saidbase, said other arm and said base including separate pivot pins forengaging an adjusting spindle, said adjusting spindle is inclined whenengaged with said pins at an angle relative to the vertical axis of saidbase.

8. An injection molding apparatus as defined in claim 7, wherein saidseparate pivot pins are disposed approximately at the same distance fromsaid pivot means.

9. An injection molding apparatus as defined in claim 2, wherein saidarms means further comprises a pivot arm which branches off at an anglein the area of the pivot means, said pivot arm including means at itsfree end for engaging one end of a setting spindle, the other endo'fsaid setting spindle including means for engaging said base, both ofsaid means for engaging adapted so that actuation of said spindle meanscauses said arm means to pivot at said pivot means.

10. An injection molding apparatus as defined in claim 9 wherein thefree end of said plvot arm and the base both include pivot pins forengaging said threaded spindle.

11. An injection molding apparatus as defined in claim 2, wherein themovable member includes engaging means provided with guide rollersmoving on hardened guide rails fastened to said second element of saidarm means, said guide rails constituting said guide means 12. Apparatusfor injection molding, comprising in combination: 4

a. a base;

b. a mold clamping unit including a stationary member, a movable memberand means connecting said members;

0. support means for carrying said members and securing them to saidbase, said support means incuding l. a pivot portion for connecting saidsupport means to said base for pivotal movement relative thereto aboutan axis thereof;

2. parallel side members extending from said pivot portion on eitherside thereof, said side members including means for abutting said baseat least at one point spaced from said axis; that portion of each sidemember that is disposed on one side of said pivot portion constitutes astabilizing arm supporting said movable member;

3. guide means provided on and along said side members, said guide meansincluding grooves; said stationary member engaging said grooves on oneside of said pivot portion; said movable member slidably engaging saidgrooves on the other side of said pivot portion; and

d. means for longitudinally adjustably immobilizing said stationarymember on said side members.

13. An injection molding apparatus as defined in claim 12, wherein theparallel side members engaging the stationary member extend from saidpivot portion in the direction toward an injection unit coaxiallyconnected with said stationary member, and the parallel side membersengaging the movable member extend from said pivot portion in thedirection away from the injection unit. I

14. An injection molding apparatus as defined in claim 12, wherein thegrooves in the parallel side members which engage'the stationary memberare formed by angled extensions of the side members.

15. An injection molding apparatus as defined in claim 12, wherein theguide grooves of each pair of parallel side members are adapted so thatsaid stationary member is engageable with either pair of side members.

16. An injection molding apparatus as defined in claim 15, wherein thesupporting means is symmetrical on both sides of said pivot portion withrespect to said guide grooves.

17. An injection molding apparatus as defined in claim 16 including apivot pin connecting said pivot portion to said base, said pivot pin canbe withdrawn from its connection with the base so that the supportingframe can be rotated through and then reinserted to connect thesupporting frame to the base. 7

l8. An injection molding apparatus as defined in claim 16, wherein saidsupport means further includes two pairs of connecting elements one oneach side of said pivot portion for connection of an injection unitoperating into the separating groove of a mold supported by saidclamping unit in both possible positions of said stationary member.

19. An injection molding apparatus as defined in claim 12, wherein saidsupport means is formed by a frame structure.

20. Apparatus for injection molding, comprising in combination:

a. a base;

b. a mold clamping unit including a stationary member and a movablemember and means connecting said members;

c. means for supporting said members so that said movable member can bedisposed relative to said stationary member;

d. means for connecting said supporting means to said base for pivotalmovement relative thereto about an axis thereof;

e. stabilizing means connected to said supporting means for stabilizingsaid clamping unit, said stabilizing means including means for abuttingsaid base at at least one point which is disposed at a distance fromsaid axis; and drive means connected to said base and said supportingmeans for pivoting said supporting means about an axis in one directionso that said means for abutting engages said base at said at least onepoint; said drive means including actuator means mounted on said base atan inclined angle relative to the vertical axis of said base; saidactuator means having a threaded spindle and a hydraulic motor drivinglyconnected to said threaded spindle. I I I!

1. Apparatus for injection molding, comprising in combination: a. abase; b. a mold clamping unit including a stationary member, a movablemember and means connecting said members; c. support means for carryingsaid members and securing them to said base, said support meansincluding
 1. a pivot portion for connecting said support means to saidbase for pivotal movement relative thereto about an axis thereof; 2.parallel side members extending from said pivot portion on either sidethereof, said side members including means for abutting said base atleast at one point spaced from said axis; that portion of each sidemember that is disposed on one side of said pivot portion constitutes astabilizing arm supporting said movable member;
 3. guide means providedon and along said members, said guide means including grooves; saidstationary member engaging said grooves on one side of said pivotportion; said movable member slidably engaging said grooves on the otherside of said pivot portion; said support means being symmetrical on bothsides of said pivot portion with respect to said grooves, so that saidstationary member is engageable with side members on either side of saidpivot portion; d. drive means connected to said base and said supportingmeans for pivoting said supporting means about said axis in onedirection so that said means for abutting engages said base at said atleast one point; and e. two pairs of connecting means on each side ofsaid pivot portion for the connection of said drive means in the twopossible positions of said stationary member; said two pairs ofconnecting means forming part of said support means.
 2. parallel sidemembers extending from said pivot portion on either side thereof, saidside members including means for abutting said base at least at onepoint spaced from said axis; that portion of each side member that isdisposed on one side of said pivot portion constitutes a stabilizing armsupporting said movable member;
 2. Apparatus for injection molding,comprising in combination: a. a base having an outline obtained byvertical projection; b. a mold clamping unit including a stationarymember, a movable member and means connecting said members; c. pivotmeans attached to said base; d. arm means swingable about said pivotmeans in a substantially vertical plane to selectively assume a first,or substantially horizontal position and a second position disposed atleast about 90* with respect to said first position, said arm meanshaving
 2. a second element, constituting a stabilizing arm, at least amajor part of which extending from said pivot means in a seconddirection that is opposite to said first direction; said major part ofsaid second element being located externally of said outline in saidfirst position of said arm means; said movable member supported by andtravelling along said second element during operation of said apparatus;e. guide means provided on said second element of said arm means tocooperate with said movable member for guiding the latter in its travel;and f. abutment means on said major part of said second element toengage said base in said second position of said arm means.
 2. parallelside members extending from said pivot portion on either side thereof,said side members including means for abutting said base at least at onepoint spaced from said axis; that portion of each side member that isdisposed on one side of said pivot portion constitutes a stabilizing armsupporting said movable member;
 3. guide means provided on and alongsaid side members, said guide means including grooves; said stationarymember engaging said grooves on one side of said pivot portion; saidmovable member slidably engaging said grooves on the other side of saidpivot portion; and d. means for longitudinally adjustably immobilizingsaid stationary member on said side members.
 3. An injection moldingapparatus as defined in claim 2, further comprising means for adjustablyimmobilizing said stationary member along said first portions of saidarm means.
 3. guide means provided on and along said members, said guidemeans including grooves; said stationary member engaging said grooves onone side of said pivot portion; said movable member slidably engagingsaid grooves on the other side of said pivot portion; said support meansbeing symmetrical on both sides of said pivot portion with respect tosaid grooves, so that said stationary member is engageable with sidemembers on either side of said pivot portion; d. drive means connectedto said base and said supporting means for pivoting said supportingmeans about said axis in one direction so that said means for abuttingengages said base at said at least one point; and e. two pairs ofconnecting means on each side of said pivot portion for the connectionof said drive means in the two possible positions of said stationarymember; said two pairs of connecting means forming part of said supportmeans.
 4. An injection molding apparatus as defined in claim 2, whereinsaid arm means are formed of a plurality of parallel spaced arms.
 5. Anapparatus for injection molding as defined in claim 2, wherein saidstabilizing arm is part of said stationary member.
 6. An injectionmolding apparatus as defined in claim 5, furtheR comprising a togglelever having a pivot portion and two arms; said pivot portionconstituting said pivot means; one arm of said toggle lever constitutingsaid first element of said arm means; the other arm of said toggle leverconstituting an additional stabilizing arm disposed substantially normalto said second element of said arm means, said additional stabilizingarm, when said clamping unit is vertically oriented with respect to saidbase, abuts with a free end thereof a portion of said base.
 7. Aninjection molding apparatus as defined in claim 6 wherein an adjustingspindle engages said other arm of said toggle lever and said base, saidother arm and said base including separate pivot pins for engaging anadjusting spindle, said adjusting spindle is inclined when engaged withsaid pins at an angle relative to the vertical axis of said base.
 8. Aninjection molding apparatus as defined in claim 7, wherein said separatepivot pins are disposed approximately at the same distance from saidpivot means.
 9. An injection molding apparatus as defined in claim 2,wherein said arms means further comprises a pivot arm which branches offat an angle in the area of the pivot means, said pivot arm includingmeans at its free end for engaging one end of a setting spindle, theother end of said setting spindle including means for engaging saidbase, both of said means for engaging adapted so that actuation of saidspindle means causes said arm means to pivot at said pivot means.
 10. Aninjection molding apparatus as defined in claim 9 wherein the free endof said pivot arm and the base both include pivot pins for engaging saidthreaded spindle.
 11. An injection molding apparatus as defined in claim2, wherein the movable member includes engaging means provided withguide rollers moving on hardened guide rails fastened to said secondelement of said arm means, said guide rails constituting said guidemeans.
 12. Apparatus for injection molding, comprising in combination:a. a base; b. a mold clamping unit including a stationary member, amovable member and means connecting said members; c. support means forcarrying said members and securing them to said base, said support meansincuding
 13. An injection molding apparatus as defined in claim 12,wherein the parallel side members engaging the stationary member extendfrom said pivot portion in the direction toward an injection unitcoaxially connected with said stationary member, and the parallel sidemembers engaging the movable member extend from said pivot portion inthe direction away from the injection unit.
 14. An injection moldingapparatus as defined in claim 12, wherein the grooves in the parallelside members which engage the stationary member are formed by angledextensions of the side members.
 15. An injection molding apparatus asdefined in claim 12, wherein the guide grooves of each pair of parallelside members are adapted so that said stationary member is engageablewith either pair of side members.
 16. An injection molding apparatus asdefined in claim 15, wherein the supporting means is symmetrical on bothsides of said pivot portion with respecT to said guide grooves.
 17. Aninjection molding apparatus as defined in claim 16 including a pivot pinconnecting said pivot portion to said base, said pivot pin can bewithdrawn from its connection with the base so that the supporting framecan be rotated through 180* and then reinserted to connect thesupporting frame to the base.
 18. An injection molding apparatus asdefined in claim 16, wherein said support means further includes twopairs of connecting elements one on each side of said pivot portion forconnection of an injection unit operating into the separating groove ofa mold supported by said clamping unit in both possible positions ofsaid stationary member.
 19. An injection molding apparatus as defined inclaim 12, wherein said support means is formed by a frame structure. 20.Apparatus for injection molding, comprising in combination: a. a base;b. a mold clamping unit including a stationary member and a movablemember and means connecting said members; c. means for supporting saidmembers so that said movable member can be disposed relative to saidstationary member; d. means for connecting said supporting means to saidbase for pivotal movement relative thereto about an axis thereof; e.stabilizing means connected to said supporting means for stabilizingsaid clamping unit, said stabilizing means including means for abuttingsaid base at at least one point which is disposed at a distance fromsaid axis; and f. drive means connected to said base and said supportingmeans for pivoting said supporting means about said axis in onedirection so that said means for abutting engages said base at said atleast one point; said drive means including actuator means mounted onsaid base at an inclined angle relative to the vertical axis of saidbase; said actuator means having a threaded spindle and a hydraulicmotor drivingly connected to said threaded spindle.